Intraductal Papillary Mucinous Neoplasm (IPMN) of the Pancreas: History, Myths, and Realities Between Past and Future

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is among the most clinically relevant and conceptually intricate precancerous lesions encountered in modern gastroenterology. First identified in the early 1980s as a "mucin-producing tumor," IPMN has since undergone a profound redefinition: from an obscure and poorly classified entity to a well-established precursor of pancreatic ductal adenocarcinoma (PDAC), shaped by characteristic molecular alterations such as KRAS, GNAS, and RNF43 mutations. Over the past two decades, the reported incidence of IPMN has risen sharply, a trend largely attributable to the widespread use of high-resolution cross-sectional imaging rather than a genuine increase in disease prevalence. IPMNs are categorized anatomically into main-duct (MD-IPMN), branch-duct (BD-IPMN), and mixed-type forms and histologically into gastric, intestinal, pancreatobiliary, and oncocytic subtypes, each associated with distinct malignant potential and prognostic implications. International consensus guidelines (Sendai 2006; Fukuoka 2012; Fukuoka revision 2017; Kyoto 2024) have progressively refined strategies for risk stratification and surgical decision-making. Nevertheless, significant debate persists regarding optimal surveillance intervals, thresholds for resection, and the management of low-risk branch-duct lesions. This review offers a comprehensive and critically evaluated synthesis about IPMN, spanning its historical recognition, molecular pathogenesis, epidemiology, clinical manifestations, diagnostic evaluation, pathological features, differential diagnosis, surveillance paradigms, long-term complications, associated conditions, therapeutic options, and future directions. Particular attention is given to longstanding "myths" that have influenced clinical practice and to emerging "realities" grounded in contemporary molecular and clinical evidence. Our aim is to provide physicians with a clear and updated framework for navigating the complexities of IPMN management in current practice.